CC2642R: How to write data from pheripheral to centarl

mohan prasanna R

Part Number: CC2642R

Hi ,

In simple central side , i am able to write and read data by using GATT_WriteCharValue and GATT_ReadCharValue API's

In pheripheral side there is a char value change call back function for read data while central trying to write data to pheripheral , but from pheripheral, If designer want to write any data to central means how can we implement ?

over 2 years ago

0 YiKai Chen over 2 years ago

Guru 735455 points

I don't think you can write data to BLE central which is contradict to BLE specification. It is always BLE peripheral that provide GATT service/attribute for central to read or write. As alternative, I think you can send notification or indication when there is BLE service/attribute change on BLE peripheral.

0 mohan prasanna R over 2 years ago in reply to YiKai Chen

Intellectual 680 points

where can i find get the Notification and indication example code in CC2642R SDK ?

0 Clément over 2 years ago

TI__Guru* 94028 points

Hi,

In our out of the box examples, the simple_central is configured to act as a GATT client.

Actually, the Bluetooth specifications do allow the simple_central to act as GATT server but this is not very common. If you really want to use this approach, you may want to leverage the multi_role example.

In your case, I think the right solution would rather to use the "notifications" or "indications". That way, every time the peripheral updates the GATT characteristic, the GATT client (central) will be notified. You may want to review the 4th characteristic of the out-of-the-box simple_peripheral example as it showcases this.

I hope this will help,

Best regards,

0 mohan prasanna R over 2 years ago in reply to mohan prasanna R

Intellectual 680 points

In simple central code i registered for indication/notification by GATT_RegisterForInd API ....what else to do , to receive the notification data on central side ?

0 mohan prasanna R over 2 years ago in reply to Clément

Intellectual 680 points

In Simple pheripheral side we are sending notification on 4th characteristic in a periodic time interval ........ at the same time if i want to receive the notification data in simple central side means what should i do on simple central side????

0 mohan prasanna R over 2 years ago in reply to YiKai Chen

Intellectual 680 points

0 Clément over 2 years ago in reply to mohan prasanna R

TI__Guru* 94028 points

Hi,

To enable GATT notifications, the device has to write in the Client Characteristic Configuration.

You may want to refer to our simple_serial_socket_client example showing this. (You should specifically refer to the function SimpleStreamClient_enableNotifications here)

Best regards,

0 Clément over 2 years ago in reply to Clément

TI__Guru* 94028 points

Hi,

As your initial question is answered, please make sure to mark the thread as resolved.

If you need more assistance, please open a new thread.

Best regards,

Bluetooth®︎

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CC2642R: How to write data from pheripheral to centarl